Determinants of Pneumococcal Vaccination Decision‐Making Among High‑Risk Adults: A Qualitative Study Guided by the Theoretical Domains Framework
Claire Chenwen Zhong, Mingtao Chen, Man Kin Yim, Sammi Ng, Junjie Huang, Martin C. S. WongABSTRACT
Background and Aims
Pneumococcal disease (PD) poses a substantial burden among older adults and individuals with chronic conditions, yet pneumococcal vaccination uptake remains suboptimal in Hong Kong. Understanding the psychological, social, and contextual determinants of pneumococcal vaccination decision‑making is essential for strengthening adult vaccination strategies.
Methods
A qualitative study was conducted among 24 adults from pneumococcal vaccination target groups. Semi‑structured interviews explored perceptions, motivations, and barriers related to PD and pneumococcal vaccination. Data were analysed using thematic analysis informed by the Theoretical Domains Framework (TDF). The TDF synthesizes constructs from behaviour change theories into 14 domains, enabling systematic examination of psychological, social, and contextual determinants of health behaviours.
Results
Over half of participants (13/24) expressed willingness to receive pneumococcal vaccination, though decisions were shaped by complex multi‑level influences. Trust in healthcare professionals and confidence in government recommendations, reflecting Social influences, emerged as commonly reported facilitators of vaccination. Financial support, such as subsidies or free vaccination, served as an important Reinforcement mechanism. The predominant barriers were limited understanding of pneumococcal vaccination and the vaccination programme (Knowledge), strong reliance on personal judgement in vaccination decision‐making (Social influences), and limited knowledge of PD (Knowledge). Participants also reported concerns about potential adverse effects (Beliefs about consequences), low perceived urgency (Intentions), and practical constraints, including limited accessibility of vaccination sites and appointment difficulties (Environmental context and resources), which were reported as additional barriers to vaccination.
Conclusions
Pneumococcal vaccination decision‐making among high‑risk adults was influenced by a combination of informational, psychological, social, and structural influences. Strengthening vaccine communication by healthcare professionals, improving awareness of and access to existing free or subsidised vaccination services, improving service accessibility, and delivering sustained public education may help address misconceptions, elevate perceived need, and improve pneumococcal vaccination coverage in Hong Kong.